Present day video recorders are typically a combination of a video camera with a video tape recorder which are constructed so as to be portable. They are often called camcorders or video tape recorders (VTRs). For the purposes of this application, they are referred to as video tape recorders. All of the present day portable video tape recorders known to the inventors use a video tape, usually contained within a cassette, as the recording medium. Recording is done in numerous formats, including analog BETA and VHS format, and the digital D1 format. A major disadvantage of video tape recorders is that video tape allows only linear access to a given point on the video tape. That is, if the tape has just finished recording, in order to access the beginning of a recorded session located at the beginning of the tape, the tape must be rewound. A further disadvantage of VTRs is that the physical medium, i.e. the tape, must generally be transported back to a studio for editing and broadcast, or the content transmitted to a studio facility.
The problem of linear access to video tape recordings is most evident in the field of broadcast television news. Typically, a reporting crew will go to a news location with a video tape recorder and record an event. Upon completion of recording, the tape must be rewound and then played back and transmitted, for example via satellite or microwave link, to a base station in a studio facility, where it is again recorded. At the base station, the re-recorded information can then be edited into a final news program.
Editing of moving pictures is commonly done digitally, using a non-linear computer-based editing system such as the Avid/1 Media Composer available from Avid Technology, Inc. of Tewksbury, Mass. Such a system typically requires digitization, or, conversion of analog video signals into a digital, computer-readable format. Even if the video signal is from digital video tape, linear access to the tape still presents the same problems. Tape recording, transmission and digitization are usually performed unless there is an actual live connection from the camera to the base station. Because of the delays in rewinding, playback and transmission of recorded information from a video tape, there is typically a half hour delay between the completion of recording of an event and the time an edited version of the recorded event can actually be broadcast by the base station. This delay is a significant competitive problem in broadcast news where the time to air is very important and stations strive to produce "up to the minute" news coverage and broadcast.
Today, electronic still cameras exist which record a still image on a digital magnetic medium, such as a floppy disk. Such a camera is described in U.S. Pat. No. 5,084,775, issued Jan. 28, 1991, and assigned to Sony Corporation. However, the camera described in that patent records still images only, not full motion video images. In addition, computer video capture systems exist, such as the NuVista video capture card available from RasterOps/Truevision, Inc. Such systems, however, have not been reduced to the portable form of the present invention to perform live digital capture directly from a camera.
Additionally, it has been recently suggested by those skilled in the field of moving picture recording that numerous problems with a non-linear digital moving picture recorder are insurmountable. In particular, it has been suggested that there is a large image quality trade-off with increased recording time capability. Additionally, it has been suggested that, using disk-based media, a little shake of the camera would cause a disk crash. Finally, it has been suggested that the disk media is substantially costlier than tape.